Narrative:

We were being radar vectored at the time of occurrence. Center gave us and the captain read back fly heading 030 degrees and descend and maintain 11000'. There was some light turbulence during the descent, so the captain turned on the seat belt sign. While the captain was talking to the passenger on the P/a, center requested that we expedite our descent through 13000 to maintain 11000', so I acknowledged. While passing 12000', we were instructed to immediately climb and maintain 13000', so we expedited to 13000' and the controller said we were cleared to 13000, not 11000'. The captain came back and said he read back 11000'. That was the end of the conflict.

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Original NASA ASRS Text

Title: ACFT DESCENDED BELOW INTENDED ALT ISSUED BY CTLR. NO CONFLICT.

Narrative: WE WERE BEING RADAR VECTORED AT THE TIME OF OCCURRENCE. CENTER GAVE US AND THE CAPT READ BACK FLY HDG 030 DEGS AND DSND AND MAINTAIN 11000'. THERE WAS SOME LIGHT TURB DURING THE DSNT, SO THE CAPT TURNED ON THE SEAT BELT SIGN. WHILE THE CAPT WAS TALKING TO THE PAX ON THE P/A, CENTER REQUESTED THAT WE EXPEDITE OUR DSNT THROUGH 13000 TO MAINTAIN 11000', SO I ACKNOWLEDGED. WHILE PASSING 12000', WE WERE INSTRUCTED TO IMMEDIATELY CLB AND MAINTAIN 13000', SO WE EXPEDITED TO 13000' AND THE CTLR SAID WE WERE CLRED TO 13000, NOT 11000'. THE CAPT CAME BACK AND SAID HE READ BACK 11000'. THAT WAS THE END OF THE CONFLICT.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.